1. Field of the Invention
The present invention concerns wireless communications, and more specifically, to methods of monitoring control channels in wireless communication systems and wireless devices using the same.
2. Related Art
3GPP (3rd Generation Partnership Project) TS (Technical Specification) Release 8-based LTE (long term evolution) is the potent next-generation mobile communication standard. Recently, LTE-A (LTE-advanced), based on 3GPP TS Release 10 supporting multiple carriers is under ongoing standardization efforts.
As set forth in 3GPP TS 36.211 V10.2.0 (2011-06) “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation (Release 10),” physical channels in 3GPP LTE/LTE-A may be classified into downlink channels including PDSCH (Physical Downlink Shared Channel) and PDCCH (Physical Downlink Control Channel) and uplink channels including PUSCH (Physical Uplink Shared Channel) and PUCCH (Physical Uplink Control Channel).
In order to respond to increasing data traffic, various techniques are being introduced to increase transmission capacity in mobile communication systems, such as MIMO (Multiple Input Multiple Output) enabling use of multiple antennas and multi-cell supportive carrier aggregation.
Control channels designed in 3GPP LTE/LTE-A deliver various kinds of control information. As novel techniques come out, increasing capacity of control channels is demanded together with enhancing scheduling flexibility.